// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef UI_GL_GL_SURFACE_OSMESA_H_
#define UI_GL_GL_SURFACE_OSMESA_H_

#include <stdint.h>

#include "base/macros.h"
#include "base/memory/scoped_ptr.h"
#include "ui/gfx/geometry/size.h"
#include "ui/gl/gl_surface.h"

namespace gfx {

enum OSMesaSurfaceFormat { OSMesaSurfaceFormatBGRA,
    OSMesaSurfaceFormatRGBA };

// A surface that the Mesa software renderer draws to. This is actually just a
// buffer in system memory. GetHandle returns a pointer to the buffer. These
// surfaces can be resized and resizing preserves the contents.
class GL_EXPORT GLSurfaceOSMesa : public GLSurface {
public:
    GLSurfaceOSMesa(OSMesaSurfaceFormat format, const gfx::Size& size);

    // Implement GLSurface.
    bool Initialize(GLSurface::Format format) override;
    void Destroy() override;
    bool Resize(const gfx::Size& new_size,
        float scale_factor,
        bool has_alpha) override;
    bool IsOffscreen() override;
    gfx::SwapResult SwapBuffers() override;
    gfx::Size GetSize() override;
    void* GetHandle() override;
    unsigned GetFormat() override;

protected:
    ~GLSurfaceOSMesa() override;

private:
    unsigned format_;
    gfx::Size size_;
    scoped_ptr<int32_t[]> buffer_;

    DISALLOW_COPY_AND_ASSIGN(GLSurfaceOSMesa);
};

// A thin subclass of |GLSurfaceOSMesa| that can be used in place
// of a native hardware-provided surface when a native surface
// provider is not available.
class GLSurfaceOSMesaHeadless : public GLSurfaceOSMesa {
public:
    explicit GLSurfaceOSMesaHeadless();

    bool IsOffscreen() override;
    gfx::SwapResult SwapBuffers() override;

protected:
    ~GLSurfaceOSMesaHeadless() override;

private:
    DISALLOW_COPY_AND_ASSIGN(GLSurfaceOSMesaHeadless);
};

} // namespace gfx

#endif // UI_GL_GL_SURFACE_OSMESA_H_
